Durov wrote on his personal authenticated account to the user, “No, this is a lie. Telegram didn’t block voice calls in your country, your providers/authorities did that.”

He previously tweeted on April 16 saying “Yes, we have activated calls for our users in Iran, but Iranian operators started to filter them. I think you should complain to them.”

Following Durov’s tweet, the public relations department of MCI (Hamrah-e Avval) MTN-Irancell and RighTel — Iran’s three largest mobile operators — in separate official statements announced the companies have nothing to do with blocking of any service.

Later on the service was available and worked for four days.

Last week Mahmoud Vaezi, the telecoms minister, said the ministry was studying the possible launch of Telegram calls in the country.

He said, “Telegram officials and the government are in talks about the planned launch of the service in Iran. The primary concern is its inevitable impact on the business of Iranian mobile network operators.”

Iranian mobile operators were apparently reluctant about the launch of the Telegram call service and the negative impact it can and will have on their earnings.

Whatsapp, another messaging app owned by Facebook, has offered both voice and video calling for over a year. Meanwhile, Skype, which also offers a mobile version, can do the same.